Method of making bolt blanks



Jul 22 1924.

C. F. WHITMAN METHOD OF MAKING BOLT BLANKS Filed May 24, 1925 3 Sheets-Sheet l IIHHWII jqgl.

July 22 1924. 1,502,221

c. F. WHITMAN METHOD OF MAKING BOLT BLANKS Filed May 24, 1923 3 Sheets-Sheet 2 is IA" M-J'i I i 22 i f 5: J9 o I J Z I A; 1 gf E18 59 1 iii??? 2 6 F 1 ii. 2 I j WW W 'hmm W 6 July 22 1924. 1,502,221

' a c. F. WHITMAN METHOD OF MAKING BOLT BLANKS Filed May 24, 1923 3 Sheets-Sheet 3 W/{W I? I k- P oued 6706A Patented July 22, 1924.

CHARLES F. WHITMAN,

PATENT OFFICE.

01? DETROIT, MICHIGAN.

METHOD OF MAKING BOLT BLANKS.

Application filed May 24, 1923. Serial No. 641,080.

To all whom it may concern:

Be it known that I, CHARLES F. WHITMAN,

a citizen of the United States of America,

residing at Detroit, in the county of Wayne 5 and State of Michigan, have invented certain new and useful Im rovements in Methods of Making Bolt Blan s, of which is following is a specification, reference being had therein to the accompanying drawings:

This invention relates to a method of forming bolt blanks in a four-stage multiple spindle automatic machine, and the method may be conveniently put into practice by making certain alterations in automatic screw machines which produce bolt and screw blanks. With this type of multiple spindle machine it is the present practice to form but a single bolt blank during one cycle of the machine. For instance at one step or stage a blank may be chamfered, advanced to the second stage, and turned down, and advanced to a third stage and cut 011'. With one blank per cycle of operations, it is necessary to operate the machine at an excessive 35 speed to obtain a. high production and the excessive speed racks the machine, necessitates constant adjustment and tension, and causes the machine to rapidly deteriorate.

My invention, in its broadest aspect involves means of forming bolt blanks at a high production rate without excessive speed and wear of the machine, the production rate being eight blanks per cycle or two blanks per each indexing compared to the usual one blank per cycle of operation. To do this turning down, chamfering and cutting off instrumentalities are disposed in and about a four-stage multiple spindle automatic machine so that, at certain stages, two operations may be performed in synchronism, and with the stage operations in sequence and properly timed, a large roduction of bolt blanks is attainable wit out racking the machine.

My invention will be described by the aid of the accompanying drawings, wherein Figure 1 is a plan of a portion of a multiple spindle automatic machine by which my method may be put into practice;

Fig. 2 is a cross sectional view of a portion of the machine;

Fig. 3 is a perspective view of a bracket and two holders in proximity thereto;

Fig. 4 is a diagrammatic end view of a spindle carrier explanatory of different stages of production, and

Fig. 5 is a diagrammatic view illustrating the different stages of operation.

As illustrating a machine by which my method may be carried into effect, I have selected some of the parts of a multiple spindle automatic machine which includes a spindle carrier 1 intermittently revolved by a driven shaft 2 and in the spindle carrier are a plurality of driven spindles 3 through which extends pieces of stock temporarily held by chucks 4. The pieces of stock are adapted to be intermittently advanced in the spindles and the protruding ends of the pieces of stock are adapted to be operated upon by chamfering, turning down and cut ting off instrumentalities which are movable to and from the pieces of stock. For the purposes of explaining my method I have deemed it unnecessary to illustrate that part of the machine which times or indexes the intermittent movement of the constantly revolving spindles, the advancement of the pieces of stock,and the movement oft-he various cutting instrumentalities.

The machine which I have in mind includes, in addition to the above recited elements, a bed or frame 5 provided with transverse ways 6 for tool slides 7 and 8. On the tool slide 8 is an overhanging bracket 9 having the top thereof provided with ways 10 for adjustable tool holders 11 provided with detachable tools 12 and 13, the tool 12 being used for chamfering or grooving purposes and the tool 13 for cutting off purposes, both of said tools being simultaneously used during the second stage of operations to be hereinafter described.

Under the overhanging bracket 9 is another tool holder 14 provided with a detachable tool 15 which is used for chamfering purposes.

On the tool slide 7 is a tool holder 16 provided with a detachable tool 17 used for cut ting off purposes.

Slidable on the shaft 2 is a non-rotatable slide head 18 in which revolves the shaft 2 and adjustable on the slide head 18 are diametrically opposed tool holders 19 each provided with turnin down tools, one designated 20 and the ot er 21. The tool holders cessations may be considered as stages-A, B,

/ C and D where the pieces of stock" are operated upon by the toolsof allof the tool holders.

At'the station A the ated upon simultaneous y by the tools and 20, the former chamiering or grooving a sta too piece of stock, as at 23 to form a blank 24 and an embryo blank 25. While the piece of stock is being grooved by the tool 15 the blank 24 isturned'down by the tool so that the blank will be com lete, but connected to the embryo blank y a neck portion. After theseoperations; the two blanks are advanced to station B where the tools 12 and 13 are simultaneously brought into action, the latter cutting ofi the first blank as clearly .shown in. Fig. 5 'and the tool '12 chamfering or grooving a piece of stock so that the second blank will be incondition to be turned down, which is accomplished after the piece of stock has been shifted toe 0. Upon 'bein turned down by the 21 the blankis t en shifted tostage where the'tooll'? is brought into action to cut off the second blank. 7 a

Duri

whennecessa particularly between stages D and A, an it is a parent that at each stage B and D a comp ete bolt blank 15 produced, consequently eight blanks during each cycle of operation or one revolution of the spindle carrier. It is therefore possible to obtain a large production ofblanksiwhen obviate close attention on the part of a ma- I chine operator.

nd a'small machine in which I I have in m1 your bolt blanks may be produced in two stages for small productlon, and. conse- .the above cycle of operations the. pieces 0 stock are advanced in the spindles 40 quently do not care to confine my method of orming bolt blanks or the like to any particular make of machine.

What I claim is 1. A method of formin bolt blanks in a four stage multiple spin le automatic machine, which method consists in turning down and chamfering a blank at the first stage; cutting off and chamfering a blank at the second stage; turning down a chamfered blank at the third stage, and cutting ofi a chamfered and turned down blank at the fourth stage, said operations being carried on in sequence and synchronously so eight blanks are produced in one cycle of the iece of stock is opermachine.

2. A method of forming bolt blanks in a multiple spindle machine wherein blanks are operated upon different stages and two blanks produced at a time, which method consists in turning down and chamfering a blank at one sta and cutting ofi the turned down and c amfered blank and partially forming an embryo blank at another stage.

- 3. Amethod of forming bolt blanks in a multiple spindle machine wherein blanks are-operated upon, which method consists in two blank chamfering" operations, two blank turning vdown operations, and two blank cutting of operations, said operations bein carried on in sequence and synchronous y so eight blanks are produced in one cycle of the machine.

4. A method of continuously formi bolt blanks from separated pieces of stock lntermitoently fed into operative positions and intermittently advanced from one stage to another, which method involves chamfering a. iece of stock to form blanks, one of which blanks is turned down during the chamfering operation; advancing the piece of stock ,to a stage where the piece of stock is a ain cham'fered and the turned down blan cut off; advancing the piece of stock to a stagewhere the piece of stock is again chamfered and the turned down blank cut ofi advancing the piece of stock to another position where the chamfered blank is turned down, and then advancing the turned down blank to a stage where it is cut off.

In testimony whereof I aflix my signature in presence of two witnesses.

CHARLES Witnesses:

J. M. JOHNSON, N. M. PownLL.

F. WHITMAN. 

